Time-Resolved Spectroscopy of Bulk and Thin Film Structure and Dynamics

9317198纳尔逊飞秒通过毫秒时间分辨光谱的凝聚态物质将进行了解固体和液体的结构变化的动力学。 结构 将研究玻璃形成液体和聚合物中晶相之间的相变和结构演变。 结果将根据结构变化的理论模型进行分析，这些模型描述了整个材料类别的行为，因此超越了单个材料，并根据分子模型试图解释特定材料的行为，考虑到它们的区别特征。薄膜的机械和导热性能的测量也将进行。目标是了解界面的线性机械响应、通过破坏性试验测量的非线性响应（例如剥离）以及界面化学和粘合之间的关系。薄膜聚合物的研究将产生直接的实际影响。所提出的方法允许非接触，非破坏性，快速原位测定的机械和热性能（弹性模量和损耗模量，热扩散率）的支持或不支持的聚合物薄膜使用 在 微电子，保护涂层，以及 其他应用。 如果非接触式粘附质量评估被证明是可能的，这将是一个真正的革命性的工具，应用社区。 ***

9317198 Nelson Femtosecond through millisecond time-resolved spectroscopy of condensed matter will be conducted to understand the dynamics of structural change in solids and liquids. Structural phase transitions between crystalline phases and structural evolution in glass-forming liquids and polymers will be examined. The results will be analyzed in terms of theoretical models of structural change, which describe the behavior of whole classes of materials and which therefore transcend individual materials, and in terms of molecular models which attempt to explain the behavior of specihc materials by taking their distinguishing characteristics into account. Measurements of the mechanical and thermal conductivity properties of thin films will also be performed. The goals will be to understand the relations between the linear mechanical response of the interface, the nonlinear response (e.g. peeling) measured by destructive tests, and the interface chemistry and bonding. The work on thin film polymers will have an immediate practical impact. The proposed method permits noncontact, nondestructive, rapid in situ determination of mechanical and thermal properties (elastic and loss moduli, thermal diffusivities) of supported or unsupported polymer films used in microelectronics, protective coatings, and other applications. If noncontact adhesion quality assessment proves possible, this will present a truly revolutionary tool to the applied community. ***